Conventionally, a method in which after data from an input apparatus such as a camera or an external storage apparatus such as an HDD/SDD is transferred to a main memory, a processor accesses the data in the main memory and operates arithmetics has been used.
In recent years, computer systems including an arithmetic processor mainly specialized for arithmetic in addition to a control processor configured to control an I/O apparatus such as an input apparatus or an external storage apparatus have been used. In general, the control processor and the arithmetic processor are connected to different interconnects, and the respective interconnects are connected via, e.g., a DMA (direct memory access) controller. Also, generally, each of the control processor and the arithmetic processor includes an individual main memory.
When the arithmetic processor operates arithmetics, a scheme is used in which data is first transferred from the I/O apparatus to the main memory for control under the control of the control processor. Next, the data is transferred from the main memory for control to the main memory for arithmetics by the DMA controller. Then, the arithmetic processor accesses the data on the main memory for arithmetics and operates arithmetics.
However, in the case of the above method, the amount of data transfer by the DMA controller is large, causing the problem of increasing the time required for processing.